IMPROVED METHOD FOR ANTI-CORROSION PRE-TREATMENT OF A METAL SURFACE CONTAINING STEEL, GALVANISED STEEL, ALUMINIUM, MAGNESIUM AND/OR A ZINC-MAGNESIUM ALLOY

• Main Authors: SCHATZ, Daniel, SAUER, Oliver, BIRKENHEUER, Stefan, HECKER, Carina
• Format: Patent
• Language: English; French; German
• Published: 19.08.2020
• Subjects: CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY IONIMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; METALLURGY; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION

Described herein is an improved process for an anticorrosion pretreatment of a metallic surface including steel, galvanized steel, aluminum, magnesium and/or a zinc-magnesium alloy, wherein the metallic surface is brought into contact with an aqueous composition A including a) from 0.01 to 0.5 g/l of a copolymer and the metallic surface is brought into contact with an acidic aqueous composition B including b1) a compound selected from the group consisting of titanium, zirconium and hafnium compounds, wherein the metallic surface is brought into contact i) firstly with the composition A and then with the composition B, ii) firstly with the composition B and then with the composition A and/or iii) simultaneously with the composition A and the composition B.Also described herein is a corresponding aqueous composition A, an aqueous concentrate for producing this composition, a correspondingly coated metallic surface and a method of using a correspondingly coated metallic substrate.